The structural dynamics governing collective motions in oligomeric membrane proteins play key
roles in vital biomolecular processes at cellular membranes. In this study, we present a
structural refinement approach that combines solid-state NMR experiments and molecular
simulations to accurately describe concerted conformational transitions identifying the overall
structural, dynamical, and topological states of oligomeric membrane proteins. The accuracy of
the structural ensembles generated with this method is shown to reach the statistical error
limit, and is further demonstrated by correctly reproducing orthogonal NMR data. We
demonstrate the accuracy of this approach by characterising the pentameric state of
phospholamban, a key player in the regulation of calcium uptake in the sarcoplasmic reticulum,
and by probing its dynamical activation upon phosphorylation. Our results underline the
importance of using an ensemble approach to characterise the conformational transitions that
are often responsible for the biological function of oligomeric membrane protein states.